Bet too little and you grow slowly; bet too much and you go broke. The Kelly criterion finds the fraction that maximizes long-run growth.
Kelly CriterionLive
the mathematically optimal bet size
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The Kelly criterion gives the bet fraction that maximizes long-run growth: f = (bp − q)/b. Bet less and you grow slower; bet more and volatility eventually ruins you. Many practitioners use a fraction of Kelly to tame the swings. Educational tool, not financial advice.
Reading this result: Kelly stakes 10.0% of your bankroll per bet — the fraction that maximizes long-run growth; betting more raises volatility without raising growth, and eventually courts ruin.
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How it works
The Kelly criterion maximizes the expected logarithm of wealth, giving the optimal bet fraction f = (bp − q)/b. Betting more than Kelly increases volatility and eventually guarantees ruin; many practitioners use half-Kelly to trade a little growth for much smoother returns. Educational tool, not financial advice.
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The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.